Answer:

the answer is A.
Explanation:
Using the laws of newton:
∑F = ma
where ∑F is the sumatory of forces acting in the system, m the mass and a the acelertion of the system.
Then, if the block is moving with constant velocity, its aceleration is equal to 0, so:
∑F = m(0)
∑F = 0
It means that:
F -
= 0
where F is the force applied and
is the friction force. Replacing the value of F, we get:
310N -
= 0
Finally, solving for
:

Answer: The frequency heard will be f = 275.675Hz
Explanation: When an object emitting sound is moving, it occurs a phenomenon called Doppler shift or Doppler effect. What happens is that the sound gets higher when the moving object comes closer the observer and becomes lower after it passes, This change is due to the quantity of waves that passes through an area in an unit of time.
The formula to calculate the Doppler effect is as follows
f = (
) · f₀
f is the observed frequency;
c is the speed of sound;
Vs is velocity of the source;
f₀ is the emitted frequency of source;
Substituting and calculating,
f =
· 300
f = 275.675 Hz
Thus, the frequency heard by the police officer is 275.675Hz.
<span>AnalStage. </span>According to Freud, a<span>dults fixated in this area could feel constantly out
of control or could need to be in control all the time. Pleasure focus
is on the anus, which occurs when a child learns to control bladder and bowel
movements. Fixation in this area can be caused from struggles during potty
training.</span>
Answer:
A. the left half becomes neutral while the right half remains negatively charged
Explanation:
This is because wherever light strikes the photoconductor, it transforms from an insulator into a conductor. The charge will then migrate through it and leaves its surface. By exposing the left half of the photoconductor to light, you allow its local charge to leave and it becomes neutral.
1). trajectory
2). person sitting in a chair
3). 490 meters
4). 65 m/s
5). False. The projectile's displacement, velocity, and acceleration have vertical and horizontal components, but the projectile doesn't.
6). False
7). The vertical component of a projectile doesn't change due to gravity, but the vertical components of its displacement, velocity, and acceleration do.
The vertical components do NOT equal the horizontal components.
8). Decreasing if you include the effects of air resistance. Constant if you don't. Gravity has no effect on horizontal velocity.
9). We can't see the simulation. But if the projectile doesn't have jets on it, then as it travels upward, its vertical velocity must decrease, because gravity is trying to not let it get away.
10). We can't see the simulation. But if the projectile is traveling downward, we would call that "falling", and its vertical velocity must increase, because gravity is pulling it downward.